The invention is directed to a device for mixing and spraying a mixture composed of at least two components, such as liquids, and a propellant.
Devices of this type are used wherever different types of contents have to be stored separately and may be mixed only just before being used. As an example, hair dyes and the like shall be mentioned.
Such devices are subjected to the following requirements:
constructional simplicity and correspondingly low manufacturing costs; PA1 easy and reliable manipulation; PA1 safe storage, i.e., especially any inadvertent mixing of the contents must be prevented; PA1 good mixing of the individual components. PA1 expensive two-valve design including two independently movable, but kinematically coupled dispensing tubes, i.e., an inner and an outer dispensing tube; PA1 additional problems of corrosion and fluid-tightness in the region of the dispensing valve associated with the inner container; PA1 relatively high assembly expenditure for the mutual association of inner and outer dispensing valve; PA1 separate means for retaining the dispensing valve of the inner container in the open position thereof, wherein the proper operation of these separate means is not always ensured, in particular because of the effects of corrosion.
For many applications, especially also in the case of hair dyes, it is desirable and even necessary that the mixture shall be dispensed in the form of an aerosol or foam. For these cases nothing but an aerosol device of the specified kind (spray container) is possible. There is a wide range of prior art devices which have proven more or less reliable in practise. As regards a discussion of this prior art, reference shall be made to the European Patent Application No. 82 102 599.6 published under the number 0062817, in which a further improvement of the prior art mentioned therein is described and claimed. Said improvement is characterized in that the inner container is configured as an independent aerosol container including a separate dispensing valve, wherein the inner container is subjected to a higher internal pressure than the outer container and its dispensing valve communicates with the interior of the outer container, that the dispensing valve of the inner container is kinematically coupled to the dispensing valve of the outer container in such a way that by normal actuation of the dispensing valve of the outer container the dispensing valve of the inner container is opened, and that furthermore means are provided for retaining the dispensing valve of the inner container in its open position. As such means there have been proposed retaining clips, detents, collects or the like.
A test series of devices made in accordance with the European Patent Application No. 82 102 599.6 (dual-compartment packages) has quickly shown that this device poses problems in practical use, and that for several reasons:
Additionally, the U.S. Pat. No. 3,040,991 and the CH-PS No. 382,075 are mentioned as further prior art. The device known from the first-mentioned publication comprises a dispensing valve structure which is comparable with the mentioned two-valve structure as regards the design effort. The valve body is a multi-part member, and consequently a high assembly effort is required for the mutual association of parts. Above all, however, the known valve structure is unsuitable for dispensing a liquid component from an inner container. According to the known proposal, only propellant gas is to be contained therein which upon exit from the inner container through the valve body is intended to entrain a liquid component contained in the outer container in the manner of a water jet pump.
From the second publication, i.e., the CH-PS No. 382,075, it is known to break open a sealing diaphragm of the inner container by means of the dispensing valve, i.e., by means of the dispensing tube thereof. The opening obtained thereby, however, is relatively undefined and in most cases so small that spontaneous intermixing of the components in the inner and outer container does not occur.
The present invention is based on the object of providing a device which is of simple design and yet functions extremely reliably, and in which a defined fluid communication between the inner and outer container may be established so that uniform good mixing of the components is ensured.
This object is solved in accordance with the invention by the use of only a single dispensing valve, the valve body thereof additionally having the function of the separate dispensing valve associated with the inner container as specified in the European Patent Application No. 82 102 599.6. Due to this constructional measure the device according to the instant invention has a minimum of parts while the operational reliability is even improved. There are no problems of corrosion at all in the region of the dispensing opening of the inner container which might in any way affect the opening of the inner container. Finally, with the device according to the invention a spontaneous and relatively large-sized opening of the inner container is ensured.
In another important embodiment, the inner aerosol valve according to the European Patent Application No. 82 102 599.6 is replaced by a special closure member including a sealing diaphragm adapted to be urged into the container opening by the dispensing tube of the dispensing valve, wherein means for locking the sealing diaphragm, preferably in the form of retaining ribs, cams or the like, are provided in the container opening of the inner container so as to obtain a defined fluid communication between the inner and the outer container. Accordingly, in the instant invention the sealing diaphragm is an integral part of the closure member of the inner container, wherein the latter is preferably held between the valve body of the dispensing valve and the edge of the opening of the inner container. Locking takes place, for instance, by means of a resilient element which urges the inner container including the closure member against the valve body of the dispensing valve.
In another important embodiment, it is possible, on the one hand, to fill the inner container in its already assembled state within the outer container. On the other hand, after filling of the inner container a fluid-tight seal between the interior of the inner container and the interior of the outer container is ensured. Above all, these measures are suitable for filling the inner container with the propellant.